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Reproductive cycle of the mollusk Atrina maura (Pterioidea: Pinnidae) in a coastal lagoon system
    of the Mexican South Pacific [Spanish]

Reproductive cycle of the mollusk Atrina maura (Pterioidea: Pinnidae) in a coastal lagoon system of the Mexican South Pacific [Spanish]

Abstract: Reproductive cycle of the mollusk Atrina maura (Pterioidea: Pinnidae) in a coastal lagoon system of the Mexican South Pacific. From February 1997 to February 1998, random samples of the mollusk Atrina maura were collected on a monthly basis from the Corralero-Alotengo lagoon system, Oaxaca, Mexico. The soft parts were separated from the valve, washed in situ, and placed in a Davison solution. The gonadosomatic index (GSi) and the muscle yield index (MYi) were measured, and the reproductive cycle was characterized by histological cuts. A. maura has two important reproductive periods, one from April to July and another from October to November; there is a resting period from August to September. The reproductive cycle has a direct relationship with the GSi and a reverse relationship with the MYi. There was evidence of a close relationship of the spawning and post-spawning periods with the water temperature (R = 0.991, p ≥ 0.002). Females dominate numerically throughout the year, but the difference is significant (χ²: p≥ 0.05) only in November. Rev. Biol. Trop. 55 (3-4): 839-852. Epub 2007 December, 28.
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Efecto de El Niño en los nutrientes y el carbón orgánico total de una laguna costera del Noroeste de Baja CaliforniaThe effect of El Niño on the nutrients and total organic carbon of a coastal lagoon of Northwestern Baja California

Efecto de El Niño en los nutrientes y el carbón orgánico total de una laguna costera del Noroeste de Baja CaliforniaThe effect of El Niño on the nutrients and total organic carbon of a coastal lagoon of Northwestern Baja California

Estero de Punta Banda (fig. 2) is a coastal lagoon located on the southeastern side of Todos Santos Bay, Baja California (31º42′, 31º47′N; 116º37 ′ , 116º40 ′ W). It has a main L-shaped channel, with a short arm of 3 km and a long arm of 7 km. A sand bar that is approximately 7 km long separates it from the bay, with a permanent entrance at the northern end (Pritchard et al., 1978). The climate of the region is Mediterranean, with dry summers and rainy winters. There is no permanent, above-ground fresh-water input to the Estero. Two streams appear when it rains: Las Ánimas, which flows into the middle part of the short arm, and San Carlos, into the middle part of the long arm (fig. 2). Despite the construction of a dike in 1983, which took away a considerable part of the area in the vertex of the L, reducing its tidal prism, the lagoon has basically maintained the same hydrological behaviour, with temperature, salinity and nutrient ranges very similar to those of the 1970s (Soto-Balderas and Álvarez- Borrego, 1991).
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Spatial and temporal variation of fish assemblages in a coastal lagoon of the Biosphere Reserve La Encrucijada, Chiapas, Mexico

Spatial and temporal variation of fish assemblages in a coastal lagoon of the Biosphere Reserve La Encrucijada, Chiapas, Mexico

Abstract: Composition and abundance of the ichthyofauna in estuarine and coastal lagoon systems of the South Pacific in Mexico have been scarcely studied. In particular, there is a lack of information on how environmental variables determine the spatio-temporal structure of fish assemblages in those habitats. In this study, fishes were sampled by drop net during twelve months (May 2004 - April 2005) in 22 sites distributed along the Carretas- Pereyra lagoon, located in the Biosphere Reserve La Encrucijada, Chiapas, Mexico. We recorded 11 797 indi- viduals (40 species, in 30 genera and 21 families). Dormitator latifrons was the most dominant species in terms of the Importance Value index, IV (23.05 %), followed by Lile gracilis (10.31 %), Poecilia sphenops (8.60 %) and Poecilia butleri (7.30 %). D. latifrons also accounted for more than one half of the total biomass (50.14 %). Species richness and Shannon-Wiener’s diversity indexes showed similar temporal fluctuations, reaching their highest values during the dry season. The system evidenced temporal variations in salinity, having observed four different regimes: freshwater, oligohaline, mesohaline and polyhaline. Mean richness and diversity indexes achieved their highest values during the mesohaline period. On the other hand, mean abundances (CPUE) were highest during the freshwater period. Canonical correspondence analysis (CCA) indicated that salinity and temperature were the most important environmental parameters affecting associations of fishes in terms of their abundances. Correlation analyses revealed that among the environmental variables measured in this study, trans- parency showed the most significant negative correlation with fish richness and Shannon-Wiener’s diversity index. At a local scale, results suggest that spatial and temporal distribution of fish assemblages are determined by differences in the regimes of salinity and transparency, primarily driven by freshwater input from rivers. Rev. Biol. Trop. 56 (2): 557-574. Epub 2008 June 30.
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Geochemistry of modern sediments from San Quintín coastal lagoon,  Baja California: Implication for provenance

Geochemistry of modern sediments from San Quintín coastal lagoon, Baja California: Implication for provenance

The San Quintín coastal lagoon (SQCL) is a shallow embayment located adjacent to a “regionally-rare” intra- plate-type basaltic terrain known as San Quintín volcanic fi eld (SQVF). The SQVF is a group of cinder cones that were active from Pleistocene to Holocene, and probably until historic times (Woodford, 1928; Figure 1). These rocks have an uncommon composition compared with the lithol- ogy of the Baja California peninsula. They are composed of alkaline intraplate-type basalts and contain upper mantle peridotite and lower crustal granulite xenoliths (Basu and Murthy, 1977; Rogers et al., 1985; Saunders et al., 1987; Luhr et al., 1995). Stable minerals identifi ed in the basalts are olivine, spinel inclusions, plagioclase, clinopyroxene, titanomagnetite and ilmenite (Luhr et al., 1995). Although the volcanic rocks show varying degrees of erosion and form most of the inner shoreline of SQCL, no evidence for signifi cant weathering of the basalts was found by Gorsline and Stewart (1962). These authors observed uniformity in the mineral composition throughout the bay, which, in addi- tion to the absence of rock fragments and coarse material, led them to conclude that the SQVF only contributed relatively small amounts of sediment to the lagoon.
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Size frequency distribution and growth of the crabs Callinectes arcuatus and C  bellicosus (Decapoda: Portunidae) in las Guásimas coastal lagoon, Mexico [Spanish]

Size frequency distribution and growth of the crabs Callinectes arcuatus and C bellicosus (Decapoda: Portunidae) in las Guásimas coastal lagoon, Mexico [Spanish]

Abstract: Size frequency distribution and growth of the crabs Callinectes arcuatus and C. bellicosus (Decapoda: Portunidae) in Las Guásimas coastal lagoon, Mexico. Information on size frequency distribution, the width-weight relation and growth parameters of the crabs Callinectes arcuatus and C. bellicosus is presented. The data comes from samples taken with a trawl net both day and night on a monthly basis from March 1998 to February 2000 in a coastal lagoon from Gulf of California. C. bellicosus (n= 878) was more abundant than C. arcuatus (n= 357) and its size frequency distribution presented carapace width CW ranges of 8.4-166 mm and 9-130 mm respectively. Both populations were mainly represented by juveniles (75 mm in CW) ranging from 37 to 75 mm in CW, and adults (>75 mm in CW) between 76 and 90 mm in CW. In both species the width- weight relation showed that males grow more than females, with an isometric growth tendency being observed. The growth parameters for C. arcuatus estimated using the von Bertalanffy Model, were: K= 0.84 year -1 , L∞=
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Distribution, abundance and alimentary preferences of the fish Opsanus phobetron (Batrachoididae)
  at the Chelem coastal lagoon, Yucatan, Mexico [Spanish]

Distribution, abundance and alimentary preferences of the fish Opsanus phobetron (Batrachoididae) at the Chelem coastal lagoon, Yucatan, Mexico [Spanish]

Abstract: Distribution, abundance and alimentary preferences of the fish Opsanus phobetron (Batrachoididae) at the Chelem coastal lagoon, Yucatan, Mexico. Fish are important ecological components in tropical coastal lagoons. In order to evaluate the distribution and feeding preferences of the toadfish Opsanus phobetron in the Chelem Lagoon, Yucatan, Mexico, fish samples were collected using a beach seine in eight stations distributed randomly, from March 2002 to January 2003. The components were analyzed by means of the relative abundance percentage and occurrence frequency. The trophic similarity between ontogenetic stages was determined with the Morisita Index. A total of 221 organisms were collected, with a density and biomass of 92.09 ind/100 m 2 and 930.39 g/100 m 2 respectively. The highest density and biomass were recorded in the same
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Production of the rotifer Brachionus plicatilis (Ploimida: Brachionidae)
in a Brazilian coastal lagoon

Production of the rotifer Brachionus plicatilis (Ploimida: Brachionidae) in a Brazilian coastal lagoon

Abstract: Secondary production, density and biomass fluctuations, and some reproductive aspects of the rotifer Brachionus plicatilis were studied weekly for two years in a Brazilian coastal lagoon. Food (and secondarily temperature) seemed to be the main factor involved in the summer increments. In the first summer, a mass mor- tality of fish caused changes in the phytoplankton, which switched from the dominance of Cyanophyceae to Chlorophyceae and other groups. For two months, production, density and biomass were relatively high until the recovery of the Cyanophyceae dominance. In the second summer, peaks of shorter duration and higher values of production, in comparison to the first one, were found. The contribution of resting eggs hatching, in the first summer, and the increment in parthenogenetic reproduction, in the second summer, would account for the pop- ulation increases observed. Males and mictic females occurred when densities were high.
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Benthic flora and reproduction of Batophora spp  algae (Chlorophyta: Dasycladaceae) in a polluted coastal lagoon (Chetumal Bay, Mexico) [Spanish]

Benthic flora and reproduction of Batophora spp algae (Chlorophyta: Dasycladaceae) in a polluted coastal lagoon (Chetumal Bay, Mexico) [Spanish]

Abstrac. Benthic flora and reproduction of Batophora spp. algae (Chlorophyta: Dasycladaceae) in a polluted coastal lagoon (Chetumal Bay, Mexico). The benthic flora, and the vegetative and reproductive characters of the algae Batophora oerstedii and B. occidentalis (Chlorophyta) were recorded from five sites of Chetumal Bay, Quintana Roo, Mexico. A sewage gradient has been reported along those sites. Plants were sampled in May and October 1999, which cor- responded to dry and rainy seasons, respectively. Forty taxa were found, 11 are new records for the Chetumal Bay, and 6 are new records for the Mexican Caribbean. Enteromorpha species were present in sites known as rich in organic matter (both from anthropogenic and natural sources). Batophora spp. is the dominant algae in all Chetumal Bay. However, it was absent next to sewage outfalls. The morphological characters of B. oerstedii and B. occidentalis did not change significantly along the sites reported as polluted. The length and width of gametophores, as well as the diameter of the gametangia were clearly different for both species. Different reproductive strategies may help B. oerstedii and B. occidentalis to closely coexist in the Chetumal Bay. Rev. Biol. Trop. 54(2): 341-355. Epub 2006 Jun 01.
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Estimating species richness and density of a bird community in a coastal lagoon on the Mexican Pacific

Estimating species richness and density of a bird community in a coastal lagoon on the Mexican Pacific

In this study we assess the bias in estimates of bird richness in a tropical wetland. We used 18 months of data from point counts to estimate the species richness in a coastal lagoon in Oaxaca and computed eight species richness estimators. We evaluated estimate inaccuracy using the sum of total richness that we obtained with combined sampling techniques between 2006 and 2010. We selected the richness estimator of minimum inaccuracy and used randomized species accumulation curves to investigate differences in species densities obtained with 10 and 20-minute counts. To ascertain if habitat type influenced richness estimates, we compared the bird diversity associated with contrasting mangrove and estuarine environments. The total richness for the lagoon was 185 species and the jackknife 2 richness estimator showed the minimum inaccuracy. The randomized accumulation curves of 10 and 20 minutes displayed partially overlapping confidence intervals and an increasing time lag between the count durations at equivalent densities. The rarefaction curves from contrasting habitat types showed significantly higher richness and species density in the estuary while the jackknife 2 estimator indicated similar sample coverage in both habitats. We identify important consequences of the sampling methodology that we used and conclude that point count sampling resulted in incomplete species detection but facilitated comparative analyses.
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Variation of a benthic heterotrophic bacteria community with different respiratory metabolisms
    in Coyuca de Benítez coastal lagoon (Guerrero, Mexico)

Variation of a benthic heterotrophic bacteria community with different respiratory metabolisms in Coyuca de Benítez coastal lagoon (Guerrero, Mexico)

canal between the Coyuca de Benítez lagoon (Guerrero, Mexico) and the coastal waters. At the three moments of the day studied (6 am, 2 pm and 10 pm), the oxygen concentrations in the overlying water and in the superficial sediment layer were near air-saturation in the diurnal samplings (582 µM at 6 am and 665 µM at 2 pm), and sub-satured during the night (158 µM). In the sediments, the models of vertical distribution of Eh and organic carbon distributions were very irregular due to the bio-perturbation of the benthic, meio- and macrofauna, whose activity allows the superficial organic carbon to migrate towards sediment deeper layers. Vertical distribution of the different viable bacteria populations seems to be related to the hydrodynamic patterns of the communicating canal and sediments heterogeneity. In the sediment column, the heterotrophic bacteria total number varied from 6.8 to 20.3 x 108 cells cm -3 . The highest heterotrophic bacterial biomass values were encountered during the
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Bioprospecting of fungi with antiproliferative activity from the mangrove sediment of the Tampamachoco coastal lagoon, Veracruz, Mexico

Bioprospecting of fungi with antiproliferative activity from the mangrove sediment of the Tampamachoco coastal lagoon, Veracruz, Mexico

Fungal strains were isolated from rhizosphere sediment collected from the mangrove forest at the Tampama- choco lagoon, Tuxpan, Veracruz, Mexico (21° 0.9’ N, 97° 47’ W). This mangrove forest has been affected in some areas by high salinity concentration due to the construc- tion of levees that blocked of fresh water flow from the Tuxpan River, resulting in areas ranging from 35 ‰ (pre- served area), to 65 ‰ (semi-preserved, chronically affec- ted zone) and up 140 ‰ (massive mangrove death; (Vo- vides et al., 2011). Therefore, five replicate samples were collected from the rhizosphere with a hand auger at 10- 15 cm depth and at 30 m intervals among samples. We
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Abundance, population structure and growth of Atrina maura (Bivalvia: Pinnidae) in a tropical coastal lagoon of the Mexican Pacific

Abundance, population structure and growth of Atrina maura (Bivalvia: Pinnidae) in a tropical coastal lagoon of the Mexican Pacific

Abstract: The abundance, population structure, and growth of the Pen-shell Atrina maura in the Corralero- Alotengo tropical lagoon system in Oaxaca, Mexico, were studied from February to September of 1997. An abundance analysis showed significant temporal and spatial differences (Kruskal-Wallis, p< 0.001). Two spatial groups of abundance were found in the area, one from the mouth of the lagoon system to the middle of the Pen- shell bank, and the other between the middle of the Pen-shell bank and the head of the system. Three temporal periods of abundance were found (February-April-May; July-August; March-June-September). The distribution of population size showed that benthic recruitment of A. maura occurred from February to July. Length fre- quency of A. maura is commonly wide-ranging; nevertheless, in this study Pen-shell organisms with a valve length of 15 cm were frequently found. The growth rate length was 3.7 cm/month during the dry season (February to May), and 3.5 cm/month during the rainy season (June to September). Sex ratio was maintained at 1:1 from February to May, but males were dominant from June to August, and the minimum length for repro- duction was registered at 10 cm valve length.
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Consecuencias de un forzamiento mareal tipo mixto semidiurno en una laguna costera someraThe dynamic consequences of a tidal forcing type mixed semidiurnal in a shallow coastal lagoon

Consecuencias de un forzamiento mareal tipo mixto semidiurno en una laguna costera someraThe dynamic consequences of a tidal forcing type mixed semidiurnal in a shallow coastal lagoon

The tide is the principal forcing in the dynamic of the coastal lagoons. The Estero de Punta Banda is a shallow coastal lagoon, with a mean depth of 4 m, approximately, located at the south part of the Bahia de Todos Santos from the west coast of Baja California. The tidal range is 2.2 m corresponding to a mesotidal regime; the tides are mixed mainly semidiurnal with a form number of 0.64. Using harmonic analysis, we calculated the amplitudes and phases of each constituent in the mouth and in the head, from observations, and in several points of main channel, from the output of the numerical model. The frequency bands with the higher spectral energy were primarily the semidiurnal and subsequently the diurnal. The amplitudes of the principal astronomical constituents (M 2 , K 1 , S 2 , and O 1 ) were attenuated from the mouth to the
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COMPARATIVE BIOACCUMULATION OF TRACE METALS USING SIX FILTER FEEDER ORGANISMS IN A COASTAL LAGOON ECOSYSTEM (OF THE CENTRAL EAST GULF OF CALIFORNIA)

COMPARATIVE BIOACCUMULATION OF TRACE METALS USING SIX FILTER FEEDER ORGANISMS IN A COASTAL LAGOON ECOSYSTEM (OF THE CENTRAL EAST GULF OF CALIFORNIA)

0.90 μg/g. There was not a significant correlation be- tween the Cd levels of different filter feeder species collected at single site in TL. This finding could be due to interspecies differences in Cd accumulation and detoxifying mechanisms. Other studies in filter feeders obtained from the Gulf of California showed that Cd levels were associated with anthropogenic activities. For example, Páez-Osuna et al. (1993) reported a range of 0.70 to 3.8 μ g/g in Chione sp. clams, and Ruelas- Inzunza and Páez-Osuna (2008) reported means of 7.2 μg/g in C. corteziensis and 1.1 μg/g in Balanus eburneus. Both studies obtained samples from in the Pabellón-Altata Lagoon, an area that is influenced by agricultural activities. Méndez et al. (2002) found a Cd range of 0.21 to 1.7 μ g/g in C. gnidia samples from Guaymas, an industrialized harbor area. Méndez et al. (2006) reported a Cd range of 1.5 to 11.1 μg/g for clams collected from a mining impacted area. The concentra- tions of Cd found in this study for many organisms are according with those found in the bioavailable sediment fraction (Tables 1 and 2) because highest tissue concen- trations were related with sites with highest bioavailable Cd concentrations. In this sense, only A. tuberculosa showed a significant correlation with Cd in bioavailable fraction (r0 0.70); the others filter feeder showed a tendency but was not significant (0.15 ≥p≥ 0.08). There are several different sources of Cd in the Gulf of Cal- ifornia. Delgadillo-Hinojosa et al. (2001) reported that Cd enrichments in superficial open water masses in the Gulf of California were associated with organic matter production and remineralization. Dynamic Cd levels in lagoon ecosystems may differ from those in open waters. First, primary productivity may be driven by organic matter from anthropogenic discharges, and its transfer can be linked to dominant species in the phyto- plankton. Second, sediment resuspension events may produce a rapidly remineralization of metal. Third, filter feeder organisms may acts as a trap, accumulating high levels of metal because they have low excretion rates (Phillips and Rainbow 1994; Luoma and Rainbow 2005). When consumed, filter feeders my also transfer accumulated concentrations of Cd to higher trophic levels.
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Growth, mortality and migratory pattern of white shrimp (Litopenaeus vannamei, Crustacea, Penaeidae) in the Carretas Pereyra coastal lagoon system, Mexico

Growth, mortality and migratory pattern of white shrimp (Litopenaeus vannamei, Crustacea, Penaeidae) in the Carretas Pereyra coastal lagoon system, Mexico

The annual bimodal abundance pattern of juvenile shrimp appears in synchrony with the dry season. Significant peak values were detected in January and July, though a third reduced mode was noted between February and March. Empirical knowledge on the part of local fishermen about the timing of shrimp postlarvae arrival and juvenile aggregation in the area of study, has historically established the months of maximum fishing effort in February-April and July-August, just prior to the onset of the above two processes. In the offshore waters of the Carretas-Pereyra system, shrimp spawning and planktonic immigration are processes intimately connected and pre- sumably, they also exhibit an annual bimodal pattern similar to that described for juvenile stages. The range size and age of emigrating juvenile shrimp (145 mm TL; 4.5 months) are comparable to those reported by Ramos-Cruz (2000) the Mar Muerto Lagoon, Oaxaca.
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Observations on abundance and spawning seasons of three fish families from an El Salvador coastal lagoon

Observations on abundance and spawning seasons of three fish families from an El Salvador coastal lagoon

The importance of Ariidae (marine catfish), Sciaenidae (croakers) and Gerreidae (mojarras) as dominant fish families in tropical American e st uaries and coastal lagoons has been documented in various studies on community structure. These three families are among the more important in terms of abundance and commercial value at Jiquilisco Bay, El Salvador (Phillips and Cole, 1978 ; Phillips, 1 9 8 1 ) and on the Mexican Pacific coast, they are the top carnivores in mangrove lagoons (Warburton, 1 978). León ( 1 973) considered Ariidae to be one of the most important components of his "sciaenid cornmunity" in the Gulf of Nicoya, Costa Rica, while B artels ( 1 9 8 1 ) found Sciaenidae and Ariidae to be most important in terms of biomass.
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Perception and enviromental, knowledge fo anthropogenic activities In a coastal community

Perception and enviromental, knowledge fo anthropogenic activities In a coastal community

changes is fundamental to design mitigation strategies for a sustainable use at the local, as well as at the national level (Aswani et al., 2015).It is also important to consider the traditional knowledge of the inhabitants that can set the guidelines to favor the management and sustainable use of natural resources, although unfortunately, this type of knowledge is not usually taken into account for the design of management plans and do not take into account the real social and economic needs (Báez-Ponce and Estrada-Lugo, 2014). The relationship between human beings and their environment is largely a reflection of the environmental perceptions that each individual appreciates and how much value their environment, and their knowledge provides elements that can contribute to its conservation (Olmos-Martínez, 2016; Moyano, 2009). Therefore, public participation should be focus the environmental policy (Fernández-Moreno, 2008). Nevertheless, Mexican environmental policy reflects more the perceptions, visions and interests of decision makers rather than those of the local population Subirats (1995), which may compromise the success of management plans or public programs (Olmos-Martínez, 2016; Fernández-Moreno, 2008). Given the above, there is a need to carry out research that provides information on the environmental perception of local populations, in order to make more effective the implementation of both public policies on environmental issues, as well as environmental education programs for the conservation and sustainable use of these ecosystems (Olmos- Martínez, et al., 2013; Fernández-Moreno, 2008; Subirats, 1995). The objective of this study is to know the perception and environmental knowledge of the inhabitants of the localities settled around the coastal lagoon of Nuxco, Guerrero, Mexico to identify the main anthropogenic disturbances in the locality to, what in the future will allow establish environmental education strategies for prevention and reduction of negative impacts on the environment, as well as a sustainable use of their natural resources.
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Blooms of Cochlodinium polykrikoides (Gymnodiniaceae) in the Gulf of California, Mexico

Blooms of Cochlodinium polykrikoides (Gymnodiniaceae) in the Gulf of California, Mexico

2002), and recently the diatoms Rhizosolenia debyana Peragallo 1892 (Gárate-Lizárraga et al. 2003) and Chaetoceros debilis Cleve 1894. Cochlodinium polykrikoides Margalef 1961 is a bloom dinoflagellate newly reported for this area (Gárate-Lizárraga et al. 2000), whose dis- tribution is restricted to warm and tropical waters (Steidinger and Tangen 1996). Blooms caused by C. polykrikoides have been associat- ed with massive fish kills, and is regarded as a potentially toxic dinoflagellate in Korea (Kim 1997). The purpose of this paper is to under- stand environmental conditions where C. polykrikoides proliferate in a shallow coastal lagoon located in the southwest coast of the Gulf of California.
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Conservation of coastal marine environments

Conservation of coastal marine environments

The ecologies of beaches and headlands along the Central American coasts are probably better known than those of other coastal types. Much has be en written on the zonation of animal life on both sandy beaches and rocky headlands (Stephenson and Stephenson, 1 5 ; Dahl, 4; Doty, 6; Hedgpeth, 1 0; Dexter, 5). The beach has also been considered as an emigration route for certain animals. For example, in Central America a number of crustaceans, such as land crabs (Ucides, Cardisoma, Gecracinus) must return to the sea to spawn, making annual mass migrations to the beach (Bright 1 ). Again, the story of the marine turtles, their use of tropical sandy beaches for breeding and nesting, and their near de mise through man's overexploitation for eggs, meat, and shell, is well known (carr and Giovannoli, 3). The recent efforts on the part of Costa Rica to control sea turtle exploitation, as well as the effective work of the Caribbean Conservation Corporation under the able direction of Dr .. Archie Carr in stemming the reduction of numbers and increasing the range of endangered turtle species, are prime examples of what can be done in wildlife conservation along tropical coasts. However, the increasing use of Central American and Panamanian beaches for recreation helps to deny those areas to their natural plant and animal inhabitants. Decisions must be made as to the relative priority of preserving the natural habitat or disrupting it through human use.
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Metagenomes of Mediterranean Coastal Lagoons

Metagenomes of Mediterranean Coastal Lagoons

In this work, we have compared the relative relevance of the different groups of microorganisms in two coastal lagoons, one freshwater and another hypersaline, with other related aquatic systems, in the frame- work of the main environmental features characterizing them. The analysis of the metagenomic and metacommunity data of these two hypertrophic lagoons has revealed interesting general patterns. We have discovered, using assembly of the metagenomic data, a novel, as yet uncultured, sulfur oxidizing alphaproteobacterium, that is abundant in the hypersaline Mar Menor. We also found evidence of the presence of only Synechococcus as the abundant cyanobacteria and the complete absence of Prochlorococcus, which is abundant in the parent Mediterranean water body from which Mar Menor waters are derived. Also, even the freshwaters of Albufera, though abundant in cyanobacteria, did not show any indication of presence of Pro- chlorococcus. Microscopy and sequence data of the phytoplankton revealed differences in the two lagoons, Mar Menor dominated by dinoflagellates and Albufera by chlorophytes, while diatoms were observed in both. The main distinctive characteristic of Albufera is its highly hypertrophic status. It contained a considerably different microbiota than less nutrient rich freshwaters. Importantly, canon- ical freshwater microbial groups like low GC Actinobacteria, LD12 lineage of Alphaproteobacteria and even the cosmopolitan betapro- teobacteria, Polynucleobacter, are all conspicuously absent. That cyanobacteria are a major component of hypertrophic waters (like
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